/* Copyright © 2023 - 2024 Coremail论客
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

export class Stack<T> {
   arr:Array<T> = new Array<T>();

  push(e:T) {
    this.arr.push(e);
  }
  pop():T {
    return this.arr.pop();
  }
  peek():T {
    return this.arr[this.arr.length - 1];
  }
  /**
   * 元素个数.
   * @returns
   */
  count():number {
    return this.arr.length;
  }
}